it's a weird connector.
The one side slides out, but it's only one side that slides. The other side stays put.
The hard part for a 'first timer' is that in order to get the plug to disengage you have to pull the slide a bit more and pull on the plug a bit at the same time. The last little bit of movement kind of ejects the pins from the O2-side of the connector and pushes it out of the 'car-side' of the connector. It's a bit hard to explain. I looked for a diagram or something but didn't come up with anything.
This will be much easier next time if you really grease the plastic connector up with silicone grease before you put it back together.
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1998 V70 AWD->FWD->AWD Turbo 215k+
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